Ozone Treatment as a Process of Quality Improvement Method of Rhubarb (Rheum rhaponticum L.) Petioles during Storage

The aim of the study was to identify the effects of ozone treatment reflected by the microbial, mechanical properties and selected chemical parameters during the storage of rhubarb petioles. For this purpose, after they were harvested, rhubarb petioles were treated with gaseous ozone at concentrations of 10 and 100 ppm, for the duration of 5, 15 and 30 min. Subsequently, the plant material was stored at room temperature for 14 days. After this time, the raw material was subjected to a number of chemical and mechanical tests. It was shown that the rhubarb petioles treated with ozone at a rate of 100 ppm for 30 min were characterized by the lowest loss of water content. It was also found that, compared to the control, most samples subjected to ozone treatment presented better mechanical properties, as well as higher oxidative potential and contents of polyphenols and vitamin C. Based on these findings, it was determined that ozone treatment largely increases storage stability of rhubarb

The Use of Gaseous Ozone to Reduce the Microbial Load of Rhubarb (Rheum L.) Petioles as an Additive to Craft Wheat Beers

Rhubarb (Rheum rhaponticum L.) is a valuable source of active components responsible for laxative, antibacterial, diuretic, anti-inflammatory and anti-cancer properties. On the other hand, ozone being an allotropic form of oxygen, due to its potential is a powerful antimicrobial agent. Treatment of rhubarb petioles with gaseous ozone, especially at a concentration of 50 ppm, for 30 minutes had a positive result on the microbiological stability and quality of the finished material. Sensory evaluation of prepared beers enriched without ozonated and ozonated rhubarb pulp showed that wheat beer with the addition of ozonated (50 ppm) rhubarb pulp was characterized by a balanced aroma and taste. The physico-chemical analysis of wheat beers demonstrated that the increasing concentration of ozone had an impact on, among others, increased the degree of final real attenuation (by 21.97%), decreased pH (by 18.43%) and energy value (by 36.30%), but had a negative impact on the content of ethyl alcohol (by 17.32%) compared to the control beer. Among the analyzed beers enriched with rhubarb, the beer product with the addition of ozonated (50 ppm) rhubarb was the most microbiologically stable. The research shows that wheat beers enriched with fragmented rhubarb can be a new trend to expand the range of wheat beers, and the use of gaseous ozone, especially at a concentration of 50 ppm for 30 minutes, can be a trend to extend the microbiological stability of beers, especially craft beers

Effects of Post-Harvest Ozone Treatment on Some Molecular Stability Markers of Amelanchier alnifolia Nutt. Fruit during Cold Storage

Fruits of Amelanchier alnifolia Nutt. ex M. Roem. (Nutt.) are a good source of bioactive compounds and vitamins. Due to the fact that the berries are a soft fruit, they require special procedures to increase their molecular and mechanical stability during cold storage. The study investigated the effects of ozone treatment applied cyclically (every 24 h) on selected chemical and mechanical parameters of saskatoon berries kept in storage. For this purpose, measurements were performed to assess changes in some molecular markers such as antioxidant potential, content of vitamin C, and total polyphenols, as well as microbial stress and maximum destructive force under uniaxial compression of samples. The effectiveness of the storage process was also assessed in relation to the conditions used by determining the proportion of fruit affected by diseases occurring in storage. The findings show that ozone treatment led to increased content of bioactive compounds at the initial stages of storage and resulted in decreased loss of water and bioactive compounds at the later stages. Ultimately, irrespective of the conditions applied during ozone treatment, it was observed that the growth of micro-organisms on the fruit surface was inhibited, and as a result, storage losses during the relevant period were significantly reduced

Modification of the Intensity of Compounds Biosynthesis in the Petioles of Rhubarb (Rheum rhaponticum L.) Induced by the Ozonation Process

Rhubarb (Rheum rhaponticum L.) is a vegetable that, despite many health-promoting properties, contains large amounts of oxalic acid, which has a negative impact on human health. Treatment of rhubarb petioles with gaseous ozone is one way to improve their quality by changing their chemical properties. As part of the research, an analysis of the mechanical and chemical properties of rhubarb petioles was performed. The analyzes showed that the applied doses of ozone of 10 ppm during 1, 3 and 5 minutes lowered the concentration of oxalic acid during 5 days of tests performed after the ozonation treatment. The most favorable effect on the reduction of oxalic acid, amounting to 36%, was caused by gaseous ozone at a concentration of 10 ppm during 5 minutes compared to the control. In addition, it was noted that on the 1st and 3rd day after using ozone gas, the antioxidant activity of the tested raw material increased significantly. Also on the same days of testing, the total amount of polyphenols increased as a result of the use of ozone fumigation. The largest increase in the total amount of polyphenols, amounting to 12%, was observed for a dose of 10 ppm 5 minutes on the 1st day after the ozonation treatment compared to the control variant. In turn, no positive effect of the ozonation process on the content of vitamin C and the value of destructive force during three-point bending of rhubarb leaf petioles was noted

Effect of Ozone Treatment on the Contents of Selected Bioactive Phytochemicals in Leaves of Alligator Plant <i>Kalanchoe daigremontiana</i>

The study investigated the effect of ozone treatment applied to Kalanchoe daigremontiana plants on the contents of selected phytochemicals and on markers of oxidative stress in the leaves. For this purpose, alligator plants were exposed to the gaseous ozone applied at a rate of 5 and 10 ppm for 1, 5, and 10 min. Subsequently, tests were performed to assess the ozone-treated plants for the ability to produce reactive oxygen species (ROS), and for the activation of superoxide dismutase (SOD) and catalase (CAT), i.e., enzymes responsible for the decomposition of ROS. Measurements were also carried out to determine antioxidant potential, total contents of polyphenols, and vitamin C in plants as well as their mechanical properties. The findings show that the use of controlled conditions of ozone treatment (10 ppm; 1 min) resulted in increased contents of selected bioactive compounds (enhancement of total polyphenols 79%, enhancement of antioxidant potential ABTS 55.6% and DPPH 65.8%) in the ozone-treated raw material, with no phytotoxic effects of the process observed. It was shown that a short duration of ozone treatment is related to the increased activity of SOD (max 44%) and CAT (max 18.8%), which contributes to the lower production of ROS in cells of Kalanchoe daigremontiana.</i

The Influence of Ozonation Carried Out during Vegetation on the Content of Selected Bioactive Phytochemicals and the Microbiological Load of Tubers of <i>Raphanus sativus</i> var. <i>sativus</i>

The aim of the study was to determine the effect of ozone gas fumigation on the mechanical, chemical, and microbiological parameters of radish tubers. Radish plants were grown in the ground in accordance with the principles of good agricultural practice and condition suitable for the soil and climatic conditions of south-eastern Poland. At the end of the growing season, 24 h before harvest, radish plants were exposed to a variable factor, i.e., fumigation with ozone gas at various doses (1 ppm for 1 and 5 min; 5 ppm for 1 and 5 min) in order to modify selected metabolic pathways of bioactive compounds. Then, 24 h after ozonation, radish tubers were harvested and placed in a climatic chamber with controlled conditions, i.e., 2 °C and 90% humidity. Laboratory analyses were performed during storage on days 1, 5, and 10. The ozonation used did not significantly improve the mechanical properties and water content of radish tubers. There was a beneficial effect of selected gaseous ozone doses (1 ppm for 1 and 5 min; 5 ppm for 1 min on the 10th day of storage) on the biosynthesis of selected bioactive compounds, i.e., ascorbic acid content, total polyphenol content, and antioxidant potential during storage. The most beneficial effects of the use of gaseous ozone were observed in the storage process in reducing the microbiological load of radish tubers. Among the ozonation doses used, the dose of 5 ppm for 5 min had the most beneficial effect on reducing the microbiological load. It reduced the number of yeasts and molds by 14.2% and aerobic mesophilic bacteria by 20.9% compared to the control sample on the last day of storage. Additionally, between the 5th and 10th day of storage, a significant effect of each ozone dose applied on reducing the occurrence of yeasts, molds, and mesophilic aerobic bacteria during tuber storage was noted

Analiza wybranych cech jakościowych peletów wytworzonych z surowca drzewnego

The article presents an analysis of the energy, mechanical and chemical properties of pellets made of wood material. According to the manufacturer, wood pellets were made of hard wood shredded to fractions approx. 1 mm thick and up to 3-4 mm long, and of a waste source - sawdust. Measurements of the selected properties were carried out on pellets with a diameter of 6 and 8 mm. Mechanical durability, humidity, crumble rate, ash quantity, calorific value were determined, as well as macronutrient and heavy metals content. The calorific value of pellets, with moisture content from 7.48% to 6.76% and ash content from 0.31% to 0.55%, ranged from 17.71-19.18 MJ·kg-1 , which testified to the beneficial energy use of the tested raw material. Based on the conducted research, it was found that the mechanical properties of pellets made of both sawdust and hard wood predispose them for use as boiler fuel. The tested materials met high quality standards for wood pellets used for non-industrial and industrial purposes.W artykule przedstawiono analizę właściwości energetycznych, mechanicznych oraz chemicznych peletów wytworzonych z surowca drzewnego. Pelety wg. informacji producenckich wyprodukowano z twardego drewna rozdrobnionego do frakcji o grubości około 1 mm i o długości do 3-4 mm oraz z surowica odpadowego-trocin. Pomiary wybranych właściwości przeprowadzono na peletach o średnicy 6 i 8 mm. Określono trwałość mechaniczną, wilgotność, straty okruszenia, ilość popiołu, wartość opałową oraz zawartość makroskładników i metali ciężkich. Wartość opałowa peletów o zawartości wilgotności od 7,48% do 6,76% i zawartości popiołu od 0,31% do 0,55% była w zakresie od 17,71-19,18 MJ·kg-1 i świadczyła o korzystnym wykorzystaniu energetycznym badanego surowca. Na podstawie przeprowadzonych badań stwierdzono, że właściwości mechaniczne peletów wytworzonych zarówno z trocin jak i z twardego drewna predysponują je do zastosowania jako paliwo kotłowe. Badane materiały spełniały wysokie jakościowe normy obowiązujące dla peletów drzewnych stosowanych do celów nieprzemysłowych i przemysłowych

Effects of Ozone Treatment on Microbial Status and the Contents of Selected Bioactive Compounds in Origanum majorana L. Plants

This study presents the effects of ozone treatment on microbial status and contents of selected bioactive compounds in marjoram plants. Origanum majorana L. is a widely used plant which in the course of production is affected by microbial infections. One of the ways to reduce microbial load involves application of a strong oxidant, such as ozone. In order to determine the effects of ozonation, a number of analyses were carried out including microbiological tests (aerobic colony count, yeast and mould count, and mesophilic lactic acid bacteria count) and chemical tests assessing total antioxidant potential, total polyphenols, and volatile fraction composition. Ultimately, the findings showed considerable (6-log) reduction in microbial load, with unchanged composition of headspace volatile compounds. Furthermore, the raw material obtained presented elevated the contents of the selected bioactive compounds. It was shown that the most beneficial effects are achieved when ozone treatment is applied at a rate of 1 ppm for a duration of 10 min

The Impact of Convection Drying Temperature on Content of Selected Phytochemicals in Dried Wild Garlic Leaves (Allium ursinum L.)

Wild garlic is a well-known and highly valued herbal plant. It is used fresh, unprocessed, and in the form of dried plants. The paper presents the results of the impact of the applied convection drying conditions at 30, 40 and 60°C on the parameters of the drying process as well as selected properties and composition of dried garlic obtained from wild garlic. It has been unequivocally shown that the increase in drying temperature significantly affects the content of thermally labile compounds, especially low-molecular weight antioxidants, including polyphenols and vitamin C. The analysis of the results clearly indicates that the dried plants obtained at 30°C contain relatively the highest amounts of antioxidant components and show the most volatile compounds profile similar to fresh wild garlic. However, the analysis of the parameters of drying process revealed that the temperature of the process significantly affects the time needed for the completion of drying process. The recommended of the most favourable process conditions should be based on an extended analysis and optimization of the entire process, taking into account not only the quality parameters of the dried material, but other parameters such as energy inputs and labour costs

Effect of Ozone Fumigation on Physiological Processes and Bioactive Compounds of Red-Veined Sorrel (Rumex sanguineus ssp. sanguineus)

The present study was designed to identify the effects of ozone fumigation of red-veined sorrel plants on the selected physiological parameters and contents of bioactive compounds in the plant leaves. Sorrel plants grown in a pot experiment were subjected, at the final stage of growth, to ozone fumigation at a concentration of 1 ppm (mg m&minus;3) for one, three, five, seven, and 10 min. The ozone treatment was followed with measurements performed one, four, and eight days later. The relative chlorophyll content in the leaves and selected chlorophyll fluorescence parameters (maximum quantum yield of PSII photochemistry, the maximum quantum yield of primary photochemistry and the performance index) and gas exchange parameters were assessed (net photosynthetic rate, transpiration rate, stomatal conductance, and intercellular CO2 concentration). By using the same leaves, the plant material was also assessed for the contents of bioactive compounds (total polyphenols) and for antioxidant properties (ABTS and DPPH assays). The ozone treatment did not produce adverse changes in the physiological parameters of the sorrel plants. Furthermore, no visible damage to the leaves was observed. On the other hand, the ozone fumigation induced the phenomenon of elicitation as a result of which it was observed that the ozone-treated sorrel plants had higher total polyphenol contents and greater antioxidant potential, compared to the plants of the same species grown in a traditional way without the ozone fumigation. Application of ozone fumigation in the production of Rumex sanguineus is associated with increased bioactive potential of the raw material obtained